Narrow foldable bridge



March 21, 1944. A. HEIDENREICH NARROW FOLDABLE BRIDGE Filed April '8,1940 2 Sheets-Sheet l INVENTOR rnm m m a T m a Y ms f I A March 21,1944- A. HEIDENREICH NARROW FOLDAB'LE BRIDGE Filed April 8, 1940 2Sheets-Sheet 2 Patented Mar. 21, 1944 UNITED STATES PATENT "OFFICENARROW BRIDGE Application April 8,, 1940, Serial No.-328,47.4 InArgentina March .1, 1910 7 Claims.

This invention relates to a narrow foldable bridge to be used at placeswhere either a natural or an artificial obstacle would hinderindividuals, animals or things from crossing, and particularly to beused for passing over unstable surfaces, ravines, channels, excavations,etc.., such as limited extensions of water, swamps, san'dy grounds,snow, 'morasses, etc.

More particularly the invention has for its object a narrow bridgepermitting the crossing ofia river, channel, brook or lake in a mannersuch as is afforded by a military pontoon bridge.

The invention comprises, essentially, a series of girders suitablyinterconnected by a jointlink in :such a way as to space them parallellyapart for a limited space in their unfolded condition and, vice versa,to hold .them together in their folded condition. A series of plates:ishingedly and successively arranged between the said girders tocooperate with these in forming a surface 01' floor to be used :as apathway. Inifolding the narrow bridge these plates are lifted therebypermitting the girders to be juxtaposed and --reducing the bulk of theobject to a minimum. In this manner the conveyance, storage and quickerection :of the bridge at any desired place is facilitated.

When this bridge is laid over an extension of water and reasonsofstability'would make it necessary for the same 'to be supported atintermediate points, the same may be laid-over rafts, pontoon-s,floating bodies or other equivalent means capable of supporting the sameon said liquid. In the caseof shallowwaters'orinundated plots of land,other kinds of supports such "as posts, piles, abutments, piers,sleepers, etc., may be employed-for the same purpose.

In order that the invention may be easily 'put into practice it is'shownbyway 'o'f'examplein the accompanying drawings wherein:

Fig. '1 is a fragmentary side view 'in section alongtheline -IJ f 'Fig.*2 *of one type of bridge the girders of which have for their .jointlink'a series of arms arranged in a'scissor-like manner, the bridgebeing shown'in its unfolded condition; Fig. 2 'isa plan view "of thebridge describ'edin the-foregoing figure; V

Fig. 2a is "a schematic "plan view showing the joint link of this typeof bridge;

Fig. 3 "is "a sid'eview of the same bridge in its folded condition?Fig.4 "is adetail sectional view along A-B o'f Fig-i2 on anen'largedscale;

Fig. 5 'is a longitudinal section along the line 0-1) "of 2.

The construction according .to the vmodel illustrated in Figs. 1 to 5consists of the girders I each of which is composed of two similarelements spaced apart by means of the spacers 2. Spaces 2 are formedbetween the elements.

To the upper edges of the girders l formed and arranged in the sameorder as these therearesecured the plates 3 by means of the hinges 4 soas to allow them to swing over the upper portion, .as may be seen fromFigs. v1 and 3. The width of these plates 3 should be such as (to permitthe plates to fill the gap between each successive ,pair of girders whenthe apparatus is unfolded. The said plates 3 may have their endsprovided with extensions forming a sort of wing (as 'i-ndicated by 3 inEig. 2) adapted to remain extended or be turned about hinges.

To the first and the last girder -l oi the series there are hingedlysecured, one Jinthe same man her as the other, the plates '3 whichconstitute the approach ramps of the bridge and .may .eventually serveas the walls of a box to enclose the apparatus in its folded condition,as may be inf'erred from Fig. 3.

In the type of bridge illustrated in Figs. 1 to 5 inclusive, thegirders'l are interconnected by two sets of pivoted arm's 55aoperating in thespaces 2". The arms .of each set are so pivoted to each other and to thegirders as to function in the manner of lazy tongs, as shown in Fig. 12.For example, successive girders may be interconnected by two pairs ofintersecting arms 5-511, as shown in Fig. 2a. The arms of .each pair.are pivoted together at their point of intersection, as shown at '8.The outer end of each of the intersecting arms is pivoted to oneofthegirders .by means of a fixed pivot, as shown .at Ba. The inner end ofeach of the intersecting arms pivots around a pin 6b which slides at itsends in slots! provided in the upper and lower elements of the glider'(see also Fig. 4). On each girder (except the end ones) two arms will,of course, The pivoted .at 5a and two arms will be pivoted at Eb,asshown in Figs. .2 and 15. Thus it will be seen that the pivoted armsforming the two lazy tongs are extensible in a horizontal plane which isparallel to the upper plane of thegirders.

A chain '8 extends-along the side of thelbridge and is connected to eachof .theplates .3.near that end ofthe plate w'hichisremoteifromtheh'inge'fl.

Aslide 5b is attached to the underside of-two successive girders at anypoint whereit is desired to reinforce the bridge. Each slidehasanelongated slot 50. One end of the slide maybe I'fastened to theunderside of one .glrderby a ipinliii,

and a pin 60 on an adjacent girder engages in the slot c and assists inholding the slide in place. These slides do not interfere with thefolding and unfolding of the bridge but they serve to limit itsextensibility.

In using the narrow bridge over an extension of water a series offloating bodies a (Fig. 1) is arranged thereunder at suitable intervals.The girders I will simply rest on or be suitably secured to thesefloating bodies, as the case may be, so as to assure the stability ofthe apparatus on the surface of the water and cause the same to standthe loads passing over the same. The floating bodies may be applied alsounder'the Wings 3 (Fig. 2) in order to impart the apparatus a greaterfloating capacity.

If so demanded by the circumstances, one or more of the apparatusesdescribed may be used, either one by the side of the other, or onefollowing the other, or both arrangements combined in one, thisdepending on the length and the width itis desired-to impart thepath-way constituted by these'means. e

To immobilizeand confine the narrow bridges during their use they aremoored by means of cables, ropes, anchors, etc.

' In order'to make the use of the apparatus safer this may be providedwith railings made of stanchions 9 and ropessa (Figs. 1 and 2), in themanner'as arranged for on certain vessels. The railings may be made alsoto form a whole with the narrow bridge to which eifect it Will besufficient for the ends of each girder I to perpendicularly. receive thecorresponding uprights which will then be interconnected by means of asystem of extensible arms similar to 5 and 511 (Fig. 2a) or by means ofcables, ropes, etc.

The operation'is as follows:

To fold the apparatus all that is necessary is to lift all'of the plates3 by pulling the chain 8 or by means of a simple manual operation;

Thereupon the girders I may be brought to a closely adjacentrelationship, this being an easy task since the arms 5 interconnectingthe same facilitate this operation. As is obvious, the folded apparatuswill represent an appreciable reduction of 'its extension-for whichreason it may readily be conveyed'and stored at any appropriate place.Ties and wrapping material may be used to better bundle it.

' As mentioned above, the narrow bridge may be used also in connectionwith unstable surfaces, such as swamps and morasses, as well as oncompressible plots of land or on treacherous ground or on ditch-furrowedtracts of land; in all and any of these cases it will permit the passageof vehicles without exposing them to the danger involved by soils ofthis nature.

I claim:

1. A narrow foldable bridge comprising a series of substantiallyhorizontally disposed girders arranged in parallel and successiverelationship,

an extensible series of arms connecting the said girders, said series ofarms comprising a pair of crossed arms located between each pair ofgirders and pivotally connected together where they cross, the ends ofthe crossed arms being pivotally connected to the girders between whichthe crossed arms are located and the connections between the ends of thearms and the girders permitting movement of the girders toward and awayfrom each other and allowing relative movement longitudinally of thegirder between the ends of the two arms connected to such girder, thesaid arms of the series being disposed at a level lower than that of theupper plane of the girdersand being extensible in a plane parallel tosaid upper plane of the girders, and a plate hinged to the upper portionof each of said girders.

2. A narrow foldable bridge comprising a series of substantiallyhorizontally disposed girders arranged in parallel and successiverelationship, an extensible series of arms connecting the said girders,said series of arms comprising a pair of crossed arms located betweeneach pair of girders and pivotally connected together where they cross,the ends of the crossed arms being pivotally connected to the girdersbetween which the crossed arms are located and the connections betweenthe ends of the arms and the girders permitting movement of the girderstoward and away from each other and allowing relative movementlongitudinally of the girder between the ends of the two arms connectedto such girder, the said arms of the series being disposed at a levellower than that of the upper plane of thegirders and being extensible ina plane parallel to said upper plane of the girders, a plate hinged tothe upper portion of each of said girders, and plates movably secured tothe opposite initial girders of the bridge providing approach ramps.

3. .A narrow foldable bridge comprising a series of substantiallyhorizontally disposed girders arranged in parallel and successiverelationship, an extensible series of arms connecting the said girders,said series of arms comprising a pair of crossed arms located betweeneach pair of girders and pivotally connected together where they cross,the ends of the crossed arms being pivotally connected to the girdersbetween which the crossed arms are located and the connections betweenthe ends of the arms and the girders permitting movement of the girderstoward and away from each other and allowing relative movementlongitudinally of the girder between the ends of the two arms connectedto such girder, the said armsof the series being disposed at a levellower than that of the upper plane of. the girders and being extensiblein a plane parallel to said upper plane of the girders, and a platehinged to the upper portion of each of said girders, all of the saidplates being connected to tensioning means secured thereto at a pointremote from the hinged connection.

4. A narrow foldable bridge comprising a series of substantiallyhorizontally disposed girders arranged in parallel and successiverelationship and provided at a level lower than that of the upper planeof the girders with a series of interconnecting arms having a lazy tongsconfiguration extensible in a plane parallel tosaid upper plane of thegirders and on an axis perpendicular to the axis of each of the saidgirders, said series of arms comprising a pair of crossed arms locatedbetween each pair of girders andpivotally connected together where theycross, the ends of the crossed arms being pivotally connected to thegirders between which the crossed arms are located and the connectionsbetween the ends of the arms and the girders permitting movement of thegirders toward and away from each other and allowing relative movementlongitudinally of the girder between the ends of the two arms connectedto such girder and a plate hinged to the upper .portion of each of saidgirders.

5. A narrow foldable bridge comprising a series of substantiallyhorizontally disposed girders arranged in parallel and successiverelationship and provided at a level lower than that of the.

upper plane of the girders with a series of interconnecting arms havinga lazy tongs configuraq tion extensible in a plane parallel to saidupper plane of the girders and on an axis perpendicular to the axis ofeach of the said girders, said series of arms comprising a pair ofcrossed arms located between each pair of girders and pivotallyconnected together where they cross, the ends of the crossed arms beingpivotally connected to the girders between which the crossed arms arelocated and the connections between the ends of the arms and the girderspermitting movement of the girders toward and away from each other andallowing relative movement longitudinally of the girder between the endsof the two arms connected to such girder, each of the said girders beingcomposed of two superposed spaced but connected members, the spacebetween said members serving as the housing for the ends of the saidinterconnecting arms, and a plate hinged to the upper member of each ofsaid girders.

6. A narrow foldable bridge comprising a series of substantiallyhorizontally disposed girders arranged in parallel and successiverelationship and provided at a level lower than that of the upper planeof the girders with a series of interconnecting arms having a lazy tongsconfiguration extensible in a plane parallel to said upper plane of thegirders and on an axis perpendicular to the axis of each of the saidgirders, said series of arms comprising a pair of crossed arms locatedbetween each pair of girders and pivotally connected together where theycross, the ends of the crossed arms being pivotally connected to thegirders between which the crossed arms are located and the connectionsbetween the ends of the arms and the girders permitting movement of thegirders toward and away from each other and allowing relative movementlongitudinally of the girder between the ends of the two arms connectedto such girder, reenforcing elongated plates connecting at least onepair of adjacent girders secured at one end to one of the said pair ofgirders and slidably secured to the other of said pair, and a platehinged to the upper portion of each of said girders.

7. A narrow-foldable bridge comprising a series of substantiallyhorizontally disposed girders arranged in parallel and successiverelationship, a series of connecting arms having a lazy tongsconfiguration connecting said girders, said series of arms comprising apair of crossed arms located between each pair of girders and pivotallyconnected together where they cross, the ends of the crossed arms beingpivotally connected to the girders between which the crossed arms arelocated and the connections between the ends of the arms and the girderspermitting movement of the girders toward and away from each other andallowing relative movement longitudinally of the girder between the endsof the two arms connected to such girder, said arms of the series beingextensible in a horizontal plane, a plate hinged to the upper portion ofeach of said girders, and a railing mounted on said girders andcomprising rigid uprights mounted on the girders and a flexible cableconnecting the upper ends of the uprights.

ALFREDO HEIDENREICH.

